Generally, a printer is to output various documents and pictures prepared by a computer, and classified into a dot printer, an inject printer and a laser beam printer and so on. As shown in FIG. 1, the inkjet printer includes a cartridge carrier 110 which is movably disposed at an inner side of the printer 100, a body for removably installing an ink cartridge 120 which is filled with ink, and a needle 111 for sucking the ink in the ink cartridge 120. Therefore, the ink is transferred through the needle 111 to a head 112 for ejecting the ink.
The ink cartridge may have various shapes and structures according to its kind, but generally has a predetermined shape so as to be installed in the printer. As shown in FIG. 2, the ink cartridge forms an internal body by coupling a cover 230 and a body 200 in which a receiving portion 201 is formed. A sponge 210 impregnated with the ink is disposed in the body 200. And at a lower surface of the body 200, there is formed a discharging portion 220 through which the impregnated ink is discharged. A through-hole 203 is formed at a desired portion of the cover 230 so as to supply external air to the inside of the body 200.
Therefore, when the printer 100 is operated, the cartridge carrier 110 is moved by an electric signal of a controlling part, the ink is ejected from the head 112 to print the documents and pictures. The ink in the receiving portion 201 is continuously supplied to the head 112 through the ink discharging portion 220 and the ink suction needle 111 so as to be capable of performing a continuous printing process.
However, in the conventional ink cartridge, since the sponge 210 impregnated with the ink is provided in the body 200, a body for storing the ink is reduced. Further, since an assembling process for installing the sponge 210 in the body 200 is required additionally, there is another problem that a fabricating cost is increased.
In order to solve the problems, there was proposed a solution that removes the sponge 210 from the inside of the body 200. In this case, since it is difficult to maintain an internal pressure of the cartridge constantly, there is a problem that the ink is leaked to the head, thereby deteriorating the printing quality of a printed material.
In addition, the ink filled in the ink suction needle 111 or the head 112 may be flowed backward by a change of the internal pressure of the cartridge body 200 due to a change of an internal temperature of the cartridge. Thus, there is other problem that the ink is not ejected to the head although the electric signal is input from the controlling part, or the ink is flowed to the head, thereby deteriorating the printing quality of a printed material.